Re: [PATCH] NFSD: Don't give out read delegations on exclusive creates

[Steve Dickson <SteveD@redhat.com>]

Hey Bruce,

Ping... ;-) I just pull from your for-3.11-incoming branch
and notice it was not there... 

This  really does help with  exclusive creates 
not being delayed... So you might want to consider it... 

steved.

On 15/05/13 14:51, Steve Dickson wrote:
> When an exclusive create is done with the mode bits
> set (aka open(testfile, O_CREAT | O_EXCL, 0777)) this
> causes a OPEN op followed by a SETATTR op. When a
> read delegation is given in the OPEN, it causes
> the SETATTR to delay with EAGAIN until the
> delegation is recalled.
> 
> This patch caused exclusive creates to give out
> a write delegation (which turn into no delegation)
> which allows the SETATTR seamlessly succeed.
> 
> Signed-off-by: Steve Dickson <steved@redhat.com>
> ---
>  fs/nfsd/nfs4state.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 316ec84..6b45d0e 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -3035,8 +3035,16 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh,
>  				goto out;
>  			if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
>  				flag = NFS4_OPEN_DELEGATE_WRITE;
> -			else
> -				flag = NFS4_OPEN_DELEGATE_READ;
> +			else {
> +				switch(open->op_createmode) {
> +				case NFS4_CREATE_EXCLUSIVE:
> +				case NFS4_CREATE_EXCLUSIVE4_1:
> +					flag = NFS4_OPEN_DELEGATE_WRITE;
> +					break;
> +				default:
> +					flag = NFS4_OPEN_DELEGATE_READ;
> +				}
> +			}
>  			break;
>  		default:
>  			goto out;
>